Science
Strand V
Use Scientific Knowledge from the Earth and Space Sciences in Real-World Contexts

 

Science/Strand V
Content Standard 4
All students will compare and contrast our planet and Sun to other planets and star systems; describe and explain how objects in the solar system move; explain scientific theories as to the origin of the solar system; and explain how we learn about the universe. (Solar System, Galaxy, and Universe)

 

Science/Strand V/Content Standard 4
High School

 

Science/Strand V/Content Standard 4/High School
Benchmark 3
Explain how stars and planetary systems form and how stars produce energy.

Benchmark Clarification

Based on atomic theory, scientists have explained how stars and planetary systems formed. They have also explained how stars produce energy. Heavy elements are formed as a result of fusion during supernova explosions; a series of these explosions over time has spread heavy elements randomly throughout the universe. Fusion in our Sun, a stable- state, main-sequence star, could not have created the heavy elements found in the solar system.

Stars and planets may be formed by the random coalescence (accretion from collisions) of elements or by gravitational attraction.

Students will:

  • Explain how the gravitational collapse of a cloud of gas and dust produces extreme pressure and temperature that triggers nuclear fusion
  • Explain how smaller atoms combine to make larger ones during nuclear fusion, release large quantities of energy, and form a star
  • Explain how heavy elements have been spread throughout the universe
  • Explain how components of a solar system may be formed

Key Concept / Real World Context / Instructional Example / Assessment Example / Resources

 

Science/Strand V/Content Standard 4/High School/Benchmark 3
Key Concept
Processes of formation:

  • coalescence from clouds of dust and gases by gravity
  • explosions of stars producing heavy elements
  • explosions of stars producing heavy elements:
    • hydrogen
    • helium

Production of energy

  • fusion
  • radiation

Planetary systems may form during this process

Heavy and light elements

Hot interiors of Earth-like planets

Age of the solar system

 

Science/Strand V/Content Standard 4/High School/Benchmark 3
Real World Context
Nebulas considered to be star-forming regions

Supernovas

Nuclear fusion research

 

Science/Strand V/Content Standard 4/High School/Benchmark 3
Instructional Example

Benchmark Question: What star processes are responsible for generating both energy and planetary systems?

Focus Question: What happens to mass when hydrogen atoms combine to make helium?

The teacher should review with students the process of nuclear fusion, during which heavier elements are made from lighter ones. One form of fusion involves two protons (hydrogen nuclei) and two neutrons combining to make one helium atom, a process that takes place at very high temperatures in the cores of stars.

Mass of 1 proton = 1.01 amu (atomic mass units).

Mass of 1 neutron = 1.01 amu (atomic mass units).

Students will look up the atomic mass of helium on the periodic table (He = 4.00 amu).

Students will determine the number of hydrogen atoms that combine with two neutrons to make one helium atom.

By calculation, students will compare the mass of the two hydrogen atoms and two neutrons to the mass of a single helium atom.

Students should answer the question, “Where did that mass go?”

Note: Mass is converted to the energy that powers the star.

Constructing: (SCI.I.1.HS.2), (SCI.I.1.HS.4).

Reflecting: (SCI.II.1.HS.1).

 

Science/Strand V/Content Standard 4/High School/Benchmark 3
Assessment Example

The only known life in our universe is carbon-based. Carbon has an atomic mass of 12 amu.

Each student will write an essay and answer the following questions:

  • By what process could a larger atom-like carbon have formed?
  • Which two combinations of lighter elements could explain the formation of carbon?

(Give students rubric before activity.)

Scoring Rubric

Criteria

Apprentice

Basic

Meets

Exceeds

Accuracy of description

Describes fusion as a process that produces energy.

Describes fusion as a process that produces energy in stars.

Describes fusion as a process that produces energy in stars and forms heavier elements from lighter ones.

Describes fusion as a process that produces energy in stars and forms heavier elements from lighter ones with a loss in mass.

Accuracy of data

Selects mass numbers from the periodic table.

Selects a pair of atoms smaller than carbon.

Selects one pair of atoms whose atomic masses add up to 12 amu.

Selects two different pairs of atoms whose atomic masses add up to 12 amu.

 

Science/Strand V/Content Standard 4/High School/Benchmark 3
Resources

Webliography.
http://mtn.merit.edu/mcf/SCI.V.4.HS.3.html

Astronomy Picture of the Day Archive: features a new image daily and an accompanying description.
http://antwrp.gsfc.nasa.gov/apod/archivepix.html

Pictures from the Hubble Space Telescope: features many pictures of stellar bodies outside the solar system.
http://www.stsci.edu/pubinfo/Pictures.html

Origin of the solar system.
http://hermes.astro.washington.edu/mirros/nineplanets/origin.html

Periodic Table.

Virtual Sun.
http://www.michielb.nl/sun/